power supply

I have a ? about power supplys I tested mine and it is dead
I went and bought one but it does not have the -5 volt rail, will it still work with my current MB (p4p 800-e DL)
the new PS would not turn on connected to my MB but would turn on when I used my atx power tester except it was failing the -5 volt test
I'm thinking the old PS killed my MB. if the newer PS are supposed to work with older MB

I have a ? about power supplys I tested mine and it is dead
I went and bought one but it does not have the -5 volt rail, will it still work with my current MB

The lack of a -5V rail is not significant, since that is used by only the ISA bus which your motherboard lacks, but there are other factors that affect suitability.

First, verify the wire color for pin 13 on the power supply connector, which will connect to pin 11 of the motherboard connector. Pin 13 is at a corner of the connector, beside the only blue wire present. If pin 13 uses a brown wire, the supply is not compatible. This is because the motherboard requires a +3.3V supply at that position (orange), but the power supply is using that pin for +3.3V sense.

Another factor is that older ATX power supplies of a given rating provide hotter +3.3V and +5V rails than an ATX12V supply of the same rating. Some ATX12V supplies provide half the 3.3 power than the ATX equivalent. This will almost certainly be a factor if you use an AGP videocard with a substantial power requirement, but that does not use a connector for additional power.

[H] Enthusiast rates power supplies, from their rating, you would be better off returning that Dynex and get a better name brand. here a link to the review of best buy's power supplieshttp://enthusiast.ha...TQ5MSwxLCw0MA==

Load Testing Summary

During the first half of the Dynex 400w’s advertised DC output capacity the unit was marginal in regards to its load testing results. The unit’s efficiency was certainly not great peaking at just ~79% in Test #2 at 120v but it could have been worse. However, whenever the unit was pushed beyond 200w DC the unit was a complete and utter failure, which is in stark contrast to what the 400w label on the unit promised. Indeed, the first unit blew out on the primary side and in doing so it damaged our Variac requiring replacement. To date primary side failures have typically taken out the power meter being used not the Variac. So in the end, the Dynex unit did manage to excel in one category, sadly that category was the test equipment destroying category where it somehow one upped the PowertekPro 500w which is certainly not a good thing to excel at in our estimation.